香樟凋落叶分解对3种草坪草的化感作用

为探讨白三叶(Trifolium repens)、匍匐剪股颖(Agrostis stolonifera)和沿阶草(Ophiopogon bodinieri)在香樟(Cinnamomum camphora)林下栽植的适宜性,采用培养皿萌发试验和盆栽试验,通过测定3种草坪草生长和抗性生理相关指标,综合评价3种草坪草对香樟化感的耐受性。结果表明,香樟凋落叶浸提液对3种草坪草的发芽有一定的抑制作用,其中沿阶草受香樟抑制作用最弱。随着土壤中凋落叶量的增加,3种草坪草株高、叶面积、生物量和叶片叶绿素含量均不断下降;白三叶和匍匐剪股颖的超氧化物歧化酶和过氧化物酶活性显著降低(P<0.05),过氧化氢酶活性升高,沿阶草则变化不明显;匍匐剪股颖的丙二醛含量显著升高(P<0.05),其他两种草坪草不受影响。因此,相对于白三叶和匍匐剪股颖,沿阶草对香樟凋落叶分解产生的化感胁迫效应具有更强的耐受性,可能更适宜在香樟林下种植。

Allelopathic effects of decomposing Cinnamomum camphora leaf litter on three turfgrasses

An indoor germination test and potted biological test were used to investigate whether three types of turfgrasses, including white clover (Trifolium repens), creeping bentgrass (Agrostis stolonifera), and Ophiopogon bodinieri, were suitable for planting under camphorwood (Cinnamomum camphora). The results showed that seed germination of the three turfgrasses was inhibited by the extract of camphorwood leaf litter, among which the inhibitory effect on O. bodinieri was weaker than that of the other two plants. The plant height, leaf area, biomass, and chlorophyll content of the three turfgrasses decreased with increasing content of leaf litter. The activities of superoxide dismutase and peroxidase of white clover and creeping bentgrass decreased significantly (P<0.05), and the activity of catalase increased, whereas that of O. bodinieri did not change significantly. The malondialdehyde content of creeping bentgrass was significantly increased (P<0.05), whereas that of the other two plants were not affected. Compared with white clover and creeping bentgrass, O. bodinieri displayed stronger tolerance to the allelopathic effect of camphorwood leaf litter and may be more suitable for intercropping with camphorwood.